默认情况下，GGTS 3.4已经有了 m2e 插件。
我猜，你没有为插件选择所有的依赖项，所以不能安装。
或者，防火墙可能会阻止在Eclipse中安装新的插件。我曾经遇到这个问题。

Use the marketplace in Groovy Grails Tool Suite to install Maven Integration for eclipse. But when confirming selected features, no matter I choose "Maven Integration for eclipse" ,the error remains :Cannot complete the provisioning operation. Please change your selection and try again. See below for details.

Cannot complete the install because one or more required items could not be found.
  Software being installed: Maven Development Tools 0.2.0.201401071755 (com.ifedorenko.m2e.mavendev.feature.feature.group 0.2.0.201401071755)
  Missing requirement: Maven Development Tools 0.2.0.201401071755 (com.ifedorenko.m2e.mavendev 0.2.0.201401071755) requires 'bundle org.eclipse.m2e.launching [1.5.0,2.0.0)' but it could not be found
  Cannot satisfy dependency:
    From: Maven Development Tools 0.2.0.201401071755 (com.ifedorenko.m2e.mavendev.feature.feature.group 0.2.0.201401071755)
    To: com.ifedorenko.m2e.mavendev [0.2.0.201401071755]

someone have any idea how can i resolve the problem?

By default, GGTS 3.4 already has the m2e plugin. I guess, you didn't select all dependecies for the plugin, so, it can not be installed. Or, the Firewall might block installing new plugins in the Eclipse. I faced this issue some times before.